Trinity Lakes Project Proposed Phase I Design & Construction
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Dallas City Council Trinity Lakes Project August 15, 2012 Potential Phase I Design & Construction Purpose • Explore potential construction possibilities for Phase I of the Trinity Lakes • Seek City Council direction on next steps August 15, 2012 2 Background: Balanced Vision Plan Natural Lake: • Located near I-35 • Approximately 56 acres • Characterized by a more natural setting Urban Lake: • Located near the Continental Bridge & Margaret McDermott Bridge • Approximately 90 acres • Characterized by the urban promenade August 15, 2012 3 Background: Balanced Vision Plan West Dallas Lake: • Located at Westmoreland • Approximately 128 acres • Characterized by a sprint rowing course which will serve as a recreation draw for the corridor August 15, 2012 4 Recent Background • In 2009, the City and Corps focused efforts on levee analysis to determine the geotechnical condition of the levees • In June 2012, the Corps determined the levees are more resilient than previously thought • The Corps and City are proceeding to complete the Environmental Impact Study, which includes a phasing plan to allow build- out over time of the Trinity Project August 15, 2012 5 Trinity Lakes Proposed Phasing Plan • The City’s current estimate of the Corps’ timeline for the lakes: – Design would begin following the completion of the EIS in mid-2014 – Construction would not likely begin until mid-2017 – Design and construction contingent upon federal funding • City staff is proposing an approach to accelerate Phase I of the Trinity Lakes so that portions of the lakes are complete earlier than the city’s current estimate of the Corps schedule • Staff’s phasing plan could provide citizens and visitors portions of the Urban and West Dallas Lakes as early as 2016 August 15, 2012 6 Trinity Lakes Proposed Phasing Plan • Planning details are VERY preliminary at this time • Additional research is required on a number of items in order to fully determine the feasibility of the proposed phasing plan • These are preliminary concepts and will be refined following discussions with partners and additional due diligence • Design development is necessary to provide more detailed information concerning expected costs The purpose of today’s briefing is to present a rough outline of the proposed approach and seek City Council direction on whether to proceed August 15, 2012 7 Phase I Priorities • Utilize the existing footprint of the Balanced Vision Plan lakes to align with the EIS • Provide possible flood control maintenance enhancements • Adjacency to existing neighborhoods • Complement other Trinity Project components such as Sylvan Avenue ramp to Crow Park, Continental Pedestrian Bridge/West Dallas Gateway, and Riverfront Blvd improvements • Maximize development opportunities directly related to the construction of lakes August 15, 2012 8 Proposed Phase I Urban Lake Uptown Design District Downtown West Dallas North Oak Cliff August 15, 2012 9 Proposed Phase I Urban Lake • Approx. 21 acres • Near Continental Pedestrian and Margaret Hunt Hill • Approx. 23 acres • Near Margaret McDermott Bridge and Commerce Bridge For reference, Lake Cliff is approximately 13 acres and Bachman Lake is approximately 120 acres August 15, 2012 10 Proposed Phase I Urban Lake August 15, 2012 11 Proposed Phase I Urban Lake • Estimated Cost –$33.2M – Anticipated funding - combination of 1998 and 2006 bond funds – Water source and associated costs still pending • Approximately 44 acres, providing for nearly half of the Balanced Vision Plan Urban Lake in this first phase • Contributes to a concentration of Trinity Project components either completed or underway near the downtown core to provide a draw for residents and visitors • Complements neighborhood improvement and development efforts underway or anticipated in the area • Avoids the footprint of construction for TxDOT’s Horseshoe Project August 15, 2012 12 Proposed Phase I West Dallas Lake Phase I West Dallas Lake Design District Downtown West Dallas Phase I Urban Lake North Oak Cliff August 15, 2012 13 Proposed Phase I West Dallas Lake • Approx. 21 acres • Near Westmoreland For reference, Lake Cliff is approximately 13 acres and Bachman Lake is approximately 120 acres August 15, 2012 14 Proposed Phase I West Dallas Lake August 15, 2012 15 Proposed Phase I West Dallas Lake • Estimated cost - $8M – Anticipated funding – future storm water funds – Water source and associated costs are still pending • Approximately 21 acres of the 128-acre West Dallas Lake • Supports implementation of desired operational needs to flatten levee slopes adjacent to the lake • Could be phased annually to increase the initial 21-acre construction project, depending upon funding available for flood control maintenance • Interest in building this lake within the private sector for rowing and waterskiing groups August 15, 2012 16 Phase I Linkage Opportunities • Proposed bond package includes funds to facilitate pedestrian and bicycle connections through the corridor to connect: – Victory – Design District – West Dallas – North Oak Cliff – Cedars – Fair Park August 15, 2012 17 Linkage Opportunities August 15, 2012 18 Phase I Items Requiring Further Evaluation • There are a number of key concerns that could impact the feasibility of the proposed phasing plan • Each of these will have to be fully vetted and discussed with partner agencies: – Funding constraints with use of City funds and any future credits for City’s design and construction – Water sources and permitting requirements – Potential design criteria such as geotechnical mitigation (i.e. cut off walls, clay liner for the lakes), hydraulic considerations, bench criteria and water quality considerations • Additional issues may arise following further research and due diligence August 15, 2012 19 Phase I Cost Considerations Requiring Further Evaluation • Projected costs are only estimates and will be refined once designed • City staff anticipates use of these funds to count towards our cost share requirements for the Corps’ EIS and/or the Trinity Parkway EIS August 15, 2012 20 Phase I Water Source Requiring Further Evaluation • Lakes will require a source of water to address evaporation losses and mitigate concerns related to downstream water rights • Permits from TCEQ may be required to address water rights and/or water sources – Time to process any permitting requirements by TCEQ is unknown and could be lengthy • Possible water sources could include groundwater, river water or re-use water • Cost of water sources is unknown August 15, 2012 21 Next Steps • Should City Council decide to continue on this path: – All work is contingent upon the Corps’ and Trinity Parkway’s EIS schedules • Until a Record of Decision has been received, no construction can commence on the proposed Phase I Lakes – If no fatal flaws are discovered through additional research, City Staff estimates the following design and construction timeline: • Design of these lakes could begin as early as the end of 2012 by modifying the existing Trinity Lakes Design contract • Design and permitting is estimated to last approximately 16-20 months • Construction is estimated to last approximately 18 -24 months • Timeline will be refined once additional detail is developed for the path forward August 15, 2012 22 Trinity Lakes Proposed Phasing Next Steps • Staff is seeking City Council direction to move forward with more detailed planning • If City Council chooses to direct staff to further refine proposed plan, then staff will brief City Council in 30-90 days on progress August 15, 2012 23 Discussion August 15, 2012 24 Appendix – Trinity Lakes History August 15, 2012 25 Trinity Lakes Background • In the mid-1990s, thousands of citizens and elected officials met to shape the vision and plan for: – flood protection, recreation, transportation, ecosystem restoration and economic development • In 1998, the voters approved $246M in bond funds for the Trinity River Corridor Project • The Balanced Vision Plan was approved by the City Council in December 2003 August 15, 2012 26 Trinity Lakes Background • The Recreation Component of the Balanced Vision Plan called for three lakes that also facilitate : – Flood protection through levee flattening and/or raising along areas of low spots – Transportation through provision of a multi-purpose bench for short term recreation and long term vehicular needs – Ecosystem restoration through creation of the meanders of the river and wetlands – Economic Development that would be a result of these amenities August 15, 2012 27 Trinity Lakes Background • In 2006, the City awarded a contract to design the Trinity Lakes to 35% to advance the Corps’ Environmental Impact Study – This design was done “at risk” and was intended to be part of the City’s cost share for future Corps work on the Upper Trinity River Feasibility Study • The Trinity Lakes included the: – Natural Lake – Urban Lake – West Dallas Lake August 15, 2012 28 Trinity Lakes Background • In 2007, Section 5141 of the Water Resources Development Act authorized the Dallas Floodway Project as an official stand alone Corps project – Shifted work done for the Dallas portion of the Upper Trinity River Feasibility Study to this project • In 2008, the plan was to complete the construction of the lakes, amenities and flood control improvements were intended to be complete by 2014 • In 2009, the levees were deemed unacceptable in Periodic Inspection #9 August 15, 2012 29 Trinity Lakes Background • In 2009, City Council approved a contract to investigate the condition of the levees and recommend solutions for 100-Year Flood Improvements • In Spring 2012, the City began construction of cut off walls to address the 100-Year Flood Improvements • In Summer 2012, the levees were deemed more resilient than previously thought • In 2013, the City plans to submit to certification of the levees to FEMA August 15, 2012 30 .